Skip to main content
. Author manuscript; available in PMC: 2010 Aug 30.
Published in final edited form as: J Membr Biol. 2009 Feb 26;228(1):15–31. doi: 10.1007/s00232-009-9155-7

Fig. 3.

Fig. 3

Intracellular pH (pHi) and surface (pHS) records during application and removal of 0.5 mM NH3/NH4+. a AmtB EGFP-tagged expressing oocyte. b H2O-injected oocyte. At the indicated times, we switched the extracellular solution from ND96 to 0.5 mM NH3/NH4+ and then back again. In both a and b, the purple record is pHS, the blue record is pHi, and the brown record is Vm. The vertical gray bands represent periods during which the pHS electrode was moved to the bulk ECF for calibration (fixed pH of 7.50). In H2O oocytes, the mean pHi was 7.21 ± 0.05 before and 7.17 ± 0.05 during exposure to 0.5 mM NH3/NH4+ (n = 8; p = 0.61); the comparable mean Vm values were −44 ± 2 and -40 ± 2 mV (n = 8; p = 0.14). In AmtB oocytes, the mean pHi was 7.24 ± 0.05 before and 7.21 ± 0.05 during exposure to 0.5 mM NH3/NH4+ (n = 8; p = 0.52); the comparable mean Vm values were −31 ± 4 and −30 ± 4 (n = 8; p = 0.87)